SAN FRANCISCO--If Microsoft hopes to get back in the smartphone game, it had better hope that Windows Phone 7 makes a bigger impact than it appeared to be having at one AT&T store here.

As of midday Monday, the store had sold less than half of its supply of 20 devices.

That's not to say that folks weren't lining up. Unfortunately, nearly all of the 200 people who showed up on Market Street this morning were there to snag tickets for a launch concert featuring Maroon 5, as opposed to getting their hands on one of the new phones. Microsoft did manage to make the most of the queue, requiring that concert-goers at least get a demo of Windows Phone 7 before getting their passes to the show, which takes place at the Fillmore this evening.

Customers at an AT&'T retail store in San Francisco get a hands-on demo with two Windows Phone 7 launch devices.

But only a small handful of those who lined up this morning ended up buying a phone.

The first Windows Phone 7 devices also went on sale at T-Mobile, though one could hardly tell by visiting the downtown San Francisco store. There were a few cases for the HD7, but the only Windows Phone on display was an HD2, which runs Microsoft's older Windows Mobile 6.5 software.

It turns out that particular T-Mobile store has seen such rampant theft of its working floor devices, that all the display units have been replaced with nonworking phones. But even there, there had been a problem with the display unit for the Windows Phone 7-based HD7, which had been broken by accident earlier that day. While the store was waiting to receive a replacement, it had a working HD7 available for demos. And despite not having any mention of the product in the store, it had sold roughly 7 devices by noon.

A key question remains how much push that the Windows Phones will get from the in-store sales staff at carrier stores. The AT&T store may have had several people there specifically to show off and sell the Windows phones, but the store's exterior touted only the iPhone, with no mention of the Windows Phone debut, or signage showing off the launch devices. It was the same over at T-Mobile, where there were giant banners promoting Android applications, with no indications of a Windows Phone section, or a dedicated set of accessories besides some generic screen protectors and USB chargers.

The visibility of the platform is bound to change over time, but if you had walked by either of these stores, you'd have no idea the first Windows Phone 7 devices were in stock and available for a hands-on demo.

Of course San Francisco is not the only place to get a Windows Phone 7, and reports of sales in other locations show a bit more promise for the device--especially in Europe, Australia, and Singapore where recent reports have them selling out. The same has been the case around parts of the U.S. as well, with Knoxville, Tenn.-based software developer Geoff Hudik tweeting this morning that all his local stores were sold out of Windows Phone 7 devices. The same thing was reportedly happening in Atlanta, according to Twitter user Rushabh Mehta, who said the local T-Mobile store there had sold out within 30 minutes of opening. Also worth a mention are online carrier sales of the devices, which have not yet been accounted for.

One thing that may not have gone so well for Microsoft publicly, and what's been giving it some attention, is the sidewalk chalking the company did to promote the Maroon 5 launch concert. It had done the same in New York to promote a Katy Perry show.

A Microsoft representative confirmed that the company, via one of its marketing agencies, did use chalk art in certain neighborhoods to promote the launch concerts. The chalk designs are temporary and are easily washed away with water, Microsoft said.

Microsoft had done a similar ground campaign for the launch of its Gears of War game franchise in 2006, which had been a tad more pedestrian than the company's infamous sticky butterfly viral campaign in 2002, which plastered MSN butterfly decals around Manhattan. Though neither of those cases were as bad as IBM's "Peace, Love & Linux" graffiti campaign in San Francisco, which used real spray paint and ended up costing IBM some $120,000 in city fines and clean-up costs.